Packaging machine



PACKAGING CHINE Filed m 14; 1939 2 Shaet s-Sho et' 1 IIlIlIXIIIIIl-ATTORNEY Patented Sept. 18, 1945 PACKAGING MACHINE 7 George A. Robinson,Milton, Mass, assignor to Pneumatic Scale Corporation, Limited, Quincy,Mass, a corporation of Massachusetts Application July 14, 1939, SerialNo. 284,414

3 Qlaims. ("01. 24959) This invention relates to a packaging machine andmore particularly to a container filling machine.'

The invention has for one of its objects to provide a novel and improvedpackaging machine embodying load forming mechanism in which provision ismade for controlling the machine in a novel and practical manner toprevent an insufliclent supply of material to the load formingmechanism.

A further object of the invention is to provide a novel and improvedcontainer filling machine in which predetermined volumes of material aredeposited into successive containers and in which provision is made bynovel mechanism for assuring a sufllcient supply of material to the loadforming mechanism to provide such predetermined volumes at all timesduring the opera-1 tion of the machine.

Astill further object of the invention is to provide a novel andimproved multiple station container filling machine having provision fordelivering a predetermined bulk or primary load into a container at onestation of operation and for delivering additional material to thecontainer at a final station of operation and in which provision is madeby novel mechanism for assuring a larly defined in the claims at the endof this specificatio'n.

In the drawings illustrating the preferred embodiment of the invention,Fig. l is a front elevation of a packaging machine embodying the presentinvention; Fig. 2 is a detail view of a portion of the measuringconveyor to be referred to; Fig. 3 is a view in cross-section taken onthe line 3-3 of Fig. 1; and Fig. 4 is a cross-sectional view taken onthe line 44 of Fig. 3.

In accordance with the present invention provision is made forcontrolling the operation of the machine when the supply of material tothe primary loading station falls below a predetermined rate to preventthe delivery of insufiicient amounts or loads of material into thecontainers during the operation of the machine. The invention may alsobe embodied in a two station package filling machine wherein a bulk loadis intro- 55 duced at the primary station and a drip load is added atthe final station provided with a weighing scale and in which the dripstream continues to flow until the package has reached the requiredweight. In such a machine, if the primary load falls below apredetermined minimum the drip stream will be required to flow for anunreasonably long period of time to bring the package up to the requiredweight, thereby increasing the filling time. In accordance with thepresent invention, such delay is eliminated by assuring the delivery ofthe proper quantity of material at the primary or bulk loading station.

Referring now to the drawings, for the purpose of illustration, theinvention is illustrated as embodied in a multiple station packagefilling machine which, except as hereinafter pointed out;

I vention.

In general. the machine illustrated in the drawings comprises a bulkloading station i0 adapted to deliver a. measured primary load into acontainer l2 supported beneath it upon a transfer plate I3 and betweenguide rails l5, ll. Provision is made for moving the container after ithas received its bulk load onto an intermediate platform which may bereferred to as a tapping mechanism II which operates to shake down thebulk load to settle it in the container, after which the containen isadvanced to a weighing scale I8 of the final loading station 18. Thefinal loading station comprises in part a vibratory feeder I9 and ahopper 20 adapted to deliver a stream of the 'material being weighedinto the container which has previously been supplied with the bulkload.

The empty containers are fed into the machine by a constantly driveninlet conveyor 22 until the foremost container thereon engages a fixedstop 24 and a transfer plate 26 is arranged to thereafter engage theforemost container on the inlet conveyor and push it into a positionwhere it may be engaged by one of a plurality of spaced pusher arms 28on an endless intermittently driven chain 30 by which the container ismoved beneath the bulk loading station Ill. The transfer plate 26 isarranged to operate in timed relation to the series of pusher arms 28 onthe conveyor chain 30 to intermittently feed the containers in suc-.

cession first to the bulk loading station I0, then to the tappingmechanism I4, and then onto the weighing scale I6 of the final loadingstation. Finally, after the container has received its final load, it isdischarged from the machine upon a discharge conveyor 32.

The present filling machine is particularly adapted for packagingrelatively coarse or bulky materials such as, for example, thin wafers,crackers, lump starch, elbow macaroni, etc., and is designed to handlesuch materials in a smooth and gentle manner, with a minimum breakage ofthe goods.

Referring now particularly to Fig. 3, the present bulk loading mechanismI may and preferably will comprise a measuring device including anendless driven belt conveyor 34 provided with a plurality of spacedpusher plates 36 traversable through a conduit formed by the side walls38, 40 of a hopper 42, thus forming a series of compartments or pockets43 of equal capacity. Material is supplied to the conveyor 34 in acontinuous stream from any source of supply by a belt conveyor 45running over a pulley 41 at one end and the material is arranged to flowfrom the belt 45 by gravity down an inclined chute 46 directl into thecompartments 43 on the conveyor 34. As herein shown, the inclined chute45 is pivotally mounted at its lower end upon a pin 48 supported in themachine frame and the upper end is supported through a connecting link50 by one end of a counterweighted balance beam 52 for a purpose to behereinafter disclosed.

The belt conveyor 34 is arranged to be driven intermittently in timedrelation to the movement of the containers I2, and in the operation ofthe machine, the contents of an individual compartment are deliveredthrough the hopper 42 into a container positioned beneath it during eachcycle of operation of the machine. Provision is also made in thepreferred embodiment of the invention for levelling off the material inthe top of the compartments during the operation of the machine and, asherein shown, a pair of continuously rotated brushes 54, 56 disposedabove the conveyor 34'are arranged to sweep any surplus material off thetop and in a backward direction toward the inclined chute. As hereinshown, the rotary brushes 54, 56 mounted upon shafts 58, 60respectively, are spaced apart and are arranged to be rotated togetherby a chain 62 running over sprockets 64, 65. Each brush may comprise adrum 68 having secured thereto a plurality of radially arranged bladesI0 provided with serrated edges 12 and the blades may preferably be madeof a flexible material such as leather so as to effect a gentle combingaction upon the goods and to prevent breakage thereof, particularly whenfragile goods such as thin wafers or crackers are being run. The brushesare arranged to be driven continuously through connections from the maindriving shaft I of the machine, as will be described.

As illustrated in detail in Figs. 2 and 4, the conveyor belt 34, whichmay comprise any suitable fiexible belting material, forms the bottom ofthe measuring compartments. The belt is supported along its longitudinaledges by the turned in lower edges 1!, I3 of the side walls 38, 40. Eachpusher plate 35, which may be made of metal, is attached to the flexiblebelt by bolts I4 extending'through a base I6 and an an elongated crossbar 80 disposed below the belt, the latter forming part of the drivingconnections to the belt. As herein shown, each cross bar 80 s, connectedat either end to driving chains 82, 84 which are arranged to run oversimilar sprockets 8B, 88 mounted upon cross shafts 90, 92 respectively.

Provision is made for guiding the chains 82, 84 along the upper run inorder to support the pusher plates 36 during their travel through theupper or measuring run of the conveyor and as herein shown, the upperrun of each chain is guided between spaced upper rails 94, 96. Provisionis also made for retaining the pusher plates 36 in a vertical positionwith respect to the flexible belt during their travel through theconduit, and to this end, each cross bar is provided with an angularlyextended arm 98 carrying a roller I00 at its outer end, which isarranged to engage the top of a rail 94 whereby to prevent the plates 35from tipping backward when they engage the material being delivered tothe belt as clearly illustrated in Fig. 2. Provision is also made forintermittently moving the belt 34 through connections from the maindriving shaft I5 as will be described, and as illustrated in Fig. 3,each intermittent movement of the belt will advance a pusher plate 36 asufllcient distance to permit the contents of a compartment to bedischarged into a container. During its travel through the lower orreturn run, the chains 32, 84 are supported upon guide rails I 02 toguide the pusher plates and the belt through the easing I04 enclosingthe lower run, the latter forming a part of the hopper 42.

As above stated, in general, the construction and mode of operation ofthe illustrated two station filling machine, except as herein pointedout, may comprise that of the known automatic filling machine as fullyillustrated and described in the patent to Cleaves, to which referenceis made. For an understanding of the operation of such machine, it maybe stated that the machine is operated in successive cycles. During thefirst part of each cycle in the operation of the machine, the bulkloading, tapping and final weighing operations described take place.After the container I2 on the weighin scale I5 has reached its fullweight, the second part of the cycle is permitted to begin and thecontainer moving mechanism is actuated to advance a container to theposition previously occupied by the preceding one. In other words, anunfilled container is fed into position under the bulk loading mechanismand the container with its bulk load is fed onto the weighing scale I6and the completely weighed container is fed onto the discharge conveyor32 to be discharged from the machine.

Referring now to Figs. 1 and 3, the main driving shaft I5 of the machineis rotated continuously through any usual or preferred source of power,herein shown as an electric motor I06 whose pulley I08 is connected by abelt III] to a pulley H2. The pulley H2 is secured to one end of anintermediate shaft II4 journaled in the bearings of a bracket IISmounted on the machine frame. The other end of the intermediate shaft H4is provided with a bevel pinion II8 which meshes with a bevel gear I20mounted upon the main shaft I5. As illustrated in Fig. l, the rotarybrushes 54, 56 are driven continuously through a sprocket I 22 fast onthe main shaft I5 and which is connected by a chain I24 to a sprocketI26 fast on the shaft 58, the latter being supported in the side framesI28, I30 mounted upon the machine frame.

In order to intermittently drive the conveyor belt 34 provision is madefor controlling the drivmg connections through the usual pawl andratchet control mechanism, indicated generally at I82 which is adaptedto be engaged to rotate one half revolution with the main shaft I6 atthe end of the package moving period of operation. As hereinillustrated, a cam I34 rotatable with the ratchet mechanism In isarranged to cooperate with a roller I56 carried by one arm I38 of abell-crank pivoted at on the machine frame. The roller is urged intoengagement with its cam by a spring I42, and as shown in Fig. 1, thesecond arm I44 of the bell-crank is operatively connected to a clutchmember I46 slidingly mounted on and arranged to rotate with the mainshaft I5. During the container filling cycle of operation, the clutchmember I46 is moved into cooperative engagement with a sprocket I50loosely mounted upon the shaft and as herein shown, the sprocket I60 isconnected by a chain I52 to a sprocket I54 fast upon the conveyor shaft90. The cam I34 is designed to hold the clutch member I46 and sprocketI50 in engagement for a suflicient period of time to advance the belt-34 to deliver a measured load into a container positioned upon theplatform I3 whereupon the clutch is disengaged.

During the bulk loading operation, as above described, a previouslyloaded container positioned. upon the weighing scale I6 is receiving itsdrip or final load from the hopper 20. When the container has receivedits full weight, the control mechainsm, indicated generally at I56 isactuated to close a shutter I58 cutting off the drip stream and to startthe package moving cycle of operation through connections indicatedgenerally at I60 and as fully illustrated and described in the patent toCleaves above referred to.

Referring now to Fig. 3, the goods being introduced into the measuringcompartments 43 are normally delivered thereto in a continuous andsubstantially uniform stream from the point of supply by the belt 45 andthrough the inclined chute 46. As herein shown, the balance beam 52supporting one end of the chute 46 is mounted upon knife edges I62 in astandard supported upon the machine frame and is provided with acounterweight I64 at its other end. When the material fiowing throughthe chute 46 passes at a normal rate of flow and in an amount sufficientto fill the compartments 43, the weight of the material willcounterbalance the beam 52 and hold the beam in a horizontal positionagainst a stop member I68, as shown in Fig, 3. When, however, the rateat which the material passes through the chute falls below the desiredpredetermined minimum, then the counterweight I64 will ovenbalance thebeam causing the latter to be rocked to an angular position.

Provision is made for interrupting the circuit to the motor I06 when thebalance beam 52 is thus rocked, in order to stopthe machine and asherein shown, a mercury switch I10 forming part of the circuit isattached to the balance beam 52. The switch I10 is arranged to be closedto permit the machine to run when the balance beam is disposed in ahorizontal position as shown and to be opened when the balance beam isrocked, whereby the power supply to the motor is cut off. As illustratedin Fig, 3, the circuit to the motor I06 includes the leads I12, I14

' the latter being connected directly to the motor and the lead I12being connected to the mercury switch, the circuit being completed :bythe lead I16 running from the mercury switch to the motor. An auxiliaryswitch I18 maybe provlded to out out the mercury switch when required,as when it is desired to run the remaining material out of the machineat the end of the day's 1111'1.

From the above description, it will be observed that in operation, ifthe weight of the material passing through the chute at any time fallsbelow a predetermined amount corresponding to the counterweight upon thebeam 52, the power supply will be cut off and conversely, when theweight of the material in the chute again reaches the predeterminedamount, the power will again be reestablished to start the machine. Inthis manher, it is possible to prevent an insufficient supply ofmaterial to the measuring device to thereby assure formation of auniform bulk load of material in each compartment to be delivered to theindividual containers.

While the preferred embodiment of the invention has been hereinillustrated and described it will be understood that the invention maybe embodied in other forms within the scope of the following claims.

Having thus described the invention, what is claimed is:

1. In an automatic weighing machine of the type operating in cycles, incombination, a bulk loading device having compartments of a givenvolumetric capacity, a final loading device including a scale, conveyingmeans for presenting successive containers to said loading devices toreceive the bulk load from one of said compartments, then the final loadof additional material from said final loading device to bring thecontents of the container up to a predetermined weight, means forsupplying a stream of material to the bulk loadingdevice at a ratesufiicient to fill said bulk load compartments with the desired volumeof material, and automatic means actuable to efiect stopping of saidmachine upon a given variation in the weight of a definite length ofsaid stream of material from a predetermined value so that when saidstream is of insufficient magnitude to supply the requisite volume ofmaterial to the compartments of said bulk loading device the machine isstopped, whereby said containers are filled with a predetermined weightof material in a minimum of time and the operation of the machine is notdelayed by a prolonged filling period at said final loading devicebecause of insufiicient loading of the container by said bulk loadingdevice.

2. In an automatic weighing machine of the type operating in cycles, incombination, a bulk loading device having compartments of a givenvolumetric capacity, a final loading device including a scale, conveyingmeans for presenting successive containers to said loading devices toreceive the bulk load from one of said compartments, then the final loadof additional material from said final loading device to bring thecontents of the container up to a predetermined weight, means forsupplying a stream of material to the bulk loading device at a ratesufiicient to fill said bulk load compartments with the desired volumeof material, and automatic means actuable to efiect stopping of saidmachine upon a given variation in the weight of a definite length ofsaid stream of material from a predetermined value and to effectstarting of said machine when the weight of said stream is restored sothat when said stream is of insufiicient magnitude to supply therequisite volume of material to the compartments of said bulk loadingdevice the machine is stopped and is automatically restarted when theweight of said stream is restored, whereby said containers are filledwith a predetermined weight of material in a minimum of time and theoperation of the machine is not delayed by a prolonged filling period atsaid final loading device because of insufiicient loading of thecontainer by said bulk loading device.

3. In an automatic weighing machine of the type operating in cycles suchthat the machine does not start upon a new cycle until the final loadingof the preceding cycle has been completed, in combination, volumetricbulk load forming means arranged to operate to form successive bulkloads at predetermined time intervals, a final loading device includinga scale, conveying means for presenting successive containers to thebulk load forming means, and then to the final loading device, materialfeeding means for feeding a uniform stream of material to the bulk loadforming means; said material feeding means comprising an inclined,movable conduit, counterbalancing means for supporting the conduit andthe stream of material moving therethrough, said counterbalancing meansbeing arranged to cause movement of the conduit when the weight of thematerial flowing therethrough falls slightly below a predeterminedamount, and means actuated by movement of said conduit to stop themachine immediately upon and at the start of such movement of theconduit and while a substantial volume of material is still flowingthrough said conduit, whereby containers may be filled with material ofa predetermined weight in a minimum of time and whereby the operation ofthe machine is not delayed by a prolonged filling period at the finalloading device.

GEORGE A. ROBINSON.

